Smartphones are increasingly becoming 4K, i.e. capable of working with 4 times the HD resolution. But does it really make sense to have such depth in a small screen that’s about 5 – 6″ does it really make a difference? 4K displays are visually indistinguishable from Full HD displays in a tiny 5 to 6 inch screen.

Firstly, while 4K resolution in general refers to “True 4K” at 4096 x 2160 pixels, its popular manifestation is in the form of 4K Ultra HD, at 3840 x 2160 pixels. Here is a detailed article on screen resolutions that can serve as a ready-reconer. 4k Resolution Guide

4K screens – 4096 × 2160 pixels

Quad Full HD (QFHD) / Ultra HD (UHD) screens – 3840 × 2160 pixels

Quad HD screens – 2560 × 1440 pixels

2K screens – 2048 × 1152 pixels

Full HD – 1920 × 1080

HD – 1280 × 720

Secondly, Smartphones talk of 4K in terms of recording and display, while some are capable of only recording in 4K there are a few that playback in 4K resolutions as well.